Y2O3-doped　CuAlO2　(CAO)　ceramics　with　delafossite　structure　were　prepared　by　the　solid　state　oxide　reaction　method.　X-ray　diffraction　analysis　demonstrates　that　the　most　of　the　Y3+　enter　into　the　CAO　lattice　to　occupy　Al3+　sites,　while　the　second　phase　Al5Y3O12　is　formed　due　to　the　limited　solubility　of　Y2O3　into　CAO.　The　activation　energies　derived　from　the　temperature　depending　on　bulk　conductivity　and　dielectrically　relaxation　present　a　tend　to　decrease　similarly　as　the　Y2O3　is　added.　Besides,　the　carrier　mobility　rises　gradually　as　Y2O3　is　added,　and　turns　to　sharp　augment　at　the　Y2O3　addition　reaching　to　x　=　0.04.　Hence,　at　small　Y2O3　addition,　the　emergence　of　the　insulated　Al5Y3O12　limits　the　conductivity;　on　the　other　hand,　the　sharp　augment　of　carrier　mobility　results　from　the　increase　of　the　conductivity　when　Y2O3　addition　is　over　x　=　0.04.　(C)　2015　Elsevier　B.V.　All　rights　reserved.